Project costs range from $1.9 billion to $4.5 billion depending on when repairs are done and what type of transit is added.

For example, fixing I-90, adding lanes and a bus rapid transit system would cost about $3 billion.

The most expensive option involves rebuilding and widening the tollway and allowing for the STAR line, a proposed commuter rail system along I-90 and the EJ&E Railway to be operated by Metra. The I-90 portion would run north-south from O'Hare/Rosemont to Hoffman Estates; the EJ&E section would continue east-west through Naperville to Joliet.

Tollway official are leaning toward paying for the road work via congestion pricing. The concept involves giving drivers the option of paying more to drive in an express lane during peak times or creating a carpool lane that allows single-occupancy vehicles for a fee.

But the transit element and improving the congested merge from the Jane Addams into the Kennedy Expressway aren't tollway issues alone, Lafleur told officials with the Chicago Transit Authority, Pace, Metra, the Regional Transportation Authority and Illinois Department of Transportation at the summit.

The dearth of capital dollars for such a mega-project could mean commuter rail along I-90 remains mothballed for years.

"In the short term, I don't know how we could make the financial commitment. The money's not there," Metra Director Jim LaBelle said.

Pace officials, however, committed to providing bus service on the corridor.

"If there's an available lane we can do express bus service that does multiple stops," Pace Chairman Richard Kwasneski said. "We'd be willing to look at finding dollars to do something with our equipment."